Method of positioning charges and removing drill stems from shot holes



April 21, 1959 1. P. DANIEL, SR

METHOD' CF' POSITIONING CHARGES AND REMOVING DRILL sTEMs FROM SHOT HOLES Filed Nov. so', 195e 2 Sheets-Sheet 1 Plll 21, 1959 J. P. DANIEL., SR 2,883,154

METHOD OF' POSITIONING CHARGES AND REMOVING DRILL STEMS FROM SHOT HOLES y j Filed Nov. 30,- 1956 2 Sheets-Sheet 2l 1NVENToR- 'United States. Patent O METHOD OF POSITIONING CHARGES AND RE- MOVING DRILL STEMS FROM SHOT HOLES John P. Daniel, Sr., New Orleans, La.

Application November 30, 1956, Serial No. 625,466

3 Claims. (Cl. Z55-1.8)

This invention relates in general to new and useful improvements in the drilling of shot holes for seismographic operations, and more specifically to an improved method of placing charges in shot holes after a drilling operation while the drilling tool is still in the shot hole and the removal of such drilling tool over the `detonator wire for the charge. v #This application is a continuation-in-part of my copending application Serial No. 337,835, tiled February `19, 1953, and now Patent No. 2,793,833, lgranted May 28, 1957.

` In seismographic operations, it is necessary that a large number of explosive charges be exploded beneath the .ground simultaneously. In order toaccomplish this, itis necessary that for each explosive charge a shot hole be drilled.` Unfortunately, in seismographic operations for oil fields the formation of the earth in which the shot holes -are being drilled is such that if the drilling tool were removed from the shot hole prior to the placing of the explosive charge therein, the walls of the shot hole would collapse and prevent the proper positioning ofthe explosive charge. It has therefore been necessary to place the explosive charge within the shot hole while the drilling tool remains therein and to explode such explosive charge while the drilling tool remains in the shot hole with the resultI that the drill bit and a lower portion of the drill string of the drilling tool are destroyed.

Not yonly has the heretobefore method of drilling shot holes, ythe placement of explosive charges therein and the tiring ofexplosive charges been expensive because of the destroying of material, particularly when such material must be transported to out-of-the-way places, but also extra work has beeninvolved. It is necessary that one crew drill the shot holes and place the explosive charges. The next crew then comes along and lires the explosive charges and records the results thereof. In view of the fact that many state laws require that the drill string be removed from the shot hole and also to salvage the undestroyed portion of the drill string, it is necessary that either a third crew or the rst crew must pull the drill Vstrings after the explosive charges have been red.

It is therefore the primary object of this invention to provide an improved method of drilling shot holes and placing explosive charges therein which may be accomplished with one setup and with the loss of a minimum amount or in some instances none of the drilling equipment.

Another object of this invention is to provide an improved method of anchoring a detonator Wire for an explosive charge in such a manner whereby a drilling tool may be pulled from a shot hole after the explosive charge hasbeen placed therein and over the detonator wire thereof without the detonator wire being any problem whatsoever during the removal operation.

These, together with vother objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafterdescribed :and claimed, reference being had to the Ice 2,883,154

lowered into the shot hole through the drilling tool,.

intermediate portions of the drilling tool and the earth being omitted;

Figure 2 is an enlarged sectional view showing the drilling tool elevated slightly from the bottom of a shot hole during the withdrawal operation of the drilling tool, the balled upper end of the detonator wire being shown in its frictional engagement with the drilling tool;

Figure 3 is an enlarged sectional view similar to Figure 2 and shows the nal stage of the withdrawal of the drilling tool with the explosive charge remaining in the bottom of the shot hole; and

Figure 4 is an enlarged exploded perspective view of the drill bit of the drilling tool with portions thereof being broken away in order to clearly illustrate the internal construction of the drill bit.

Referring now to the drawings in detail, it will be seen that there is illustrated in Figure 4 a special drill bit which is referred to in general by the reference numeral 10. The drill bit 10 includes 'a main drill section 12 and an auxiliary drill section 14. Also, if desired, the drill bit 10 may include a valve 16.

The main drill section 12 includes an upper cylindrical portion 18 which has depending therefrom a pair of integral teeth 20. The teeth 20 project outwardly beyond the cylindrical portion 18 and are in diametrically spaced relation. It is to be noted that the teeth 20 are longitudinally curved so that cutting tips 22 thereof are offset and are disposed at an angle to the longitudinal axisof the dri-l1 bit to effect a cutting operation.

In order that sections `of a tubing of la drill suing may be attached to the drill bit 10, the main drill section 12 is provided in the upper portion 18 thereof with internal threads 24. The threads 24 will be scattered for the particular type of tubing with which the drill bit 10 is to be used.

Extending through the main drill section 12 is a bore 26 which will be considered a flow passage. A lower part of the bore 26 is enlarged and there is formed in the interior of the main drill section 12 a downwardly facing shoulder 28. The purpose of this shoulder 28 will be set forth in detail hereinafter.

Formed in the inner faces of the individual teeth 20 are guideways 30. The guideways 30 extend longitudinally of the main drill section 12 and are in opposed diametrically spaced relation. The purpose of the guideways 30 will be set forth in detail hereinafter.

The auxiliary drill section 14 includes a body portion 32 which is generally cylindrical in outline. Formed integrally with the body portion 32 and extending downwardly therefrom are teeth 34. The teeth 34 are disposed closely adjacent to each other and are longitudinally curved so as to present cutting edges 36 which are disposed at slight angles to the longitudinal axis of the auxiliary drill section 14. It is to be noted that the teeth 34 are curved in the same manner as the teeth 20 so that the teeth 34 cooperate with the teeth 20 in a. drilling operation.

The body portion 32 is provided with an enlarged opening 38 therethrough which functions as a ilow passage. The opening 38 communicates through the bottom of the auxiliary drill section 14 by means of a bore 40. Thus drilling fluid may pass through the auxiliary drill section 14. A

In order that the auxiliary drill section 14 may be Patented Apr;A 21 ,Y 1959 positioned 'within the lower part of the main drill section 12 and to facilitate the turning of the auxiliary drill section 14 with the main drill section 12, there is formed on the exterior of the body 'portion 32 longitudinally extending ribs 42. The ribs 42 are in diametrically spaced relation and are of a size and configuration to be received within the guideways 30. Normally the pressure exertedupon the drill bit during the drilling operation twill 4be-fsufcient'to retain the auxiliary drill section 14 :withn the main drill section 12. However, if desired, suitable frangible locking means may be used to prevent the'two from separation accidentally.

When the drill bit 10 is assembled, the valve 16 is disposed above the -auxiliarydrill section 14 and is retained in 'engagement with the shoulder '28 thereby. The valve 16v includes a stiffening plate 44 which has secured to the llower'portion thereof a sealing plate 46. The sealing plate 46 has a central flapper portion 48 which is hingedly connected to the remainder thereof to facilitate the 'flow of drilling mud or other drilling 'lluids through the valve 16and at the same time prevent the reverse ow thereof.

At this time it is pointed -out that in the drilling of shot holes in kmost instances the auxiliary drill section 14 will be required. However, in certain soils, parti'cularly swampy `ground and the like, it is not necessary that there be provided the auxiliary drill vsection i114. When Vthe ground in which the shot -hole lis being drilled is ysulliciently soft, the core which would normally be forme'd'fby thecutting action of the main drill section 12 will be washed away by the drilling fluid and the necessity of the central portion of the drill which the auxiliary drill section 14 represents is eliminated. However, at such time as the auxiliary drill section 14 is required, after the drilling operation is completed, it will be removed from the main drill section 12 prior to the lowering Iof an explosive charge into the shot hole which has been -drilled in accordance with the procedure set forth in 'my copending application Serial No. 337,835. 'Ihe valve 16 will be removed at the same time.

Referring now to Figure l in particular, it will be seen that there has been drilled in the earth 50 a shot hole 552 of fa desired depth. The shot hole 52 has been diill'ed'lby utilizing a drilling tool which will be referred to 1in Igeneral by the reference numeral 54. The drilling tool -52'4 lincludes a drill string 56 and the drill bit 10, only the upper main section 12 of the drill bit 10 being used. The drill string 56 includes a plurality of individual sections of drilltubing 58 which are suitably coupled/to each other and to the drill bit 10. It is to -be understood that the terrain in which the shot hole "52 has `been drilled is relatively soft and that it has been found that the auxiliary drill section 14 may be eliminated Jduringfthe drilling operation.

`-`With the Vdrilling tool 54 remaining in the shot hole 52 to prevent the caving in of the earth formation, an explosive 'charge 60 has been lowered into the shot hole 52 down through the drilling tool 54 utilizing a detonator wire^62 which is secured to the explosive charge 60l for the purpose of exploding it at a later time. It is to Tbe' understood that the explosive charge 60 will fall readilythrough the entire drilling tool 54' due to the provision of the flow passage 26 in the main drill section 12 'andthe `normal tubular 'construction of the drill string 5'6.

When A'the detonator wire 62 is connected to the explosive charge 60, it is normally dispensed from a reel. Thus thereis provided any desired amount of the detonator wire 62. Accordingly, in accordance with the practice of `this invention, 'an extra amount of the detonator wire 62 is cut off 'from the reel and this extra amount oft'heidet'onator wire62 is formed into a ball 64 which is forced into the upper part of the drill string 56. It is to be understood that the ball 62 is of a size to frictionally engage the interior surface ofthe individual sections of .4 tubing 58 and that the friction between the ball 64 and the drill .string 56 is such that the explosive charge 60 will remain at the bottom Vof the shot hole 52 even though the drilling tool 54 is removed therefrom.

In order that the drilling tool 54 may be pulled from the shot hole 52, there is provided a lifting head 66 which is connected by a cable 68 to the draw Works (not shown) of the drilling rig (not shown) used in drilling the shot hole 52.

Referring `now to Figure 2 in particular, it will be seen that the drilling tool 54 has been moved slightly upwardly in the shot 'hole 52 in the process of being pulled from the shot hole 52. At this time the drill bit 10 has moved from above the explosive charge 60 which remains at the bottom of the shot hole 52. At the same time, the -ball 64 of the detonator wire 62 remains at its same position above the level of the ground Si) as the sections of tubing 58 pass up over the ball 64.

The individual sections of tubing 58 are removed during the pulling of Vthe drilling tool 54 in the normal manner. The pulling of the drilling tool 54 is continued in the customary manner until such time as the last section of tubing 58 and the drill bit 10 are disposed above the level of the ground 50', as is best illustrated in Figure 3. Before the 'ball 64 of the detonator Wire 62 passes out yof the drill bit 10, one may reach his hand beneath ythe drill `bit l10 and grasp the detonator wire 62. Thus, the upper end of the detonator wire 62 may be readily anchored above the surface of the ground S0.

It is pointed out atv this ktime that while the walls of the shot hole 52 have been shown as being undisturbed after the pulling of the drilling tool 54, in most instances this is not the case. Particularly in soft formations the walls of the shot hole 52 will cave in and the explosive charge 60 will be buried. This is desirable rather than detrimental inasmuch as the explosive charge 60 will be'more eie'ctive in a seismographic operation if it Vis covered and not permitted to blow back through the -shot hole 52.

It is 'to be understood vthat a plurality of shot holes S2 will y'he drilled and the explosive charges 60 placed therein by a drilling crew. This drilling crew will anchor the upper ends of the detonator Wires 62 in .a suitalble manner above the surface of the ground 50. 4Then the detonator and recording crew will follow. This second crew will connect a suitable ring device (not shown) to the upper ends of the detonator wires 62 so that a large number of the explosive charges 60 may be exploded simultaneously.

It is to be understood that when the auxiliary drill section 14 is utilized in conjunction with the main drill section 12, the only difference in the procedure set forth above willvbe that the entire drilling tool 54 will be slightly elevated above the bottom of the shot hole 52 and the valve 16 and the auxiliary drill section 14 will be removed prior to the lowering of the explosive charge 60 down through the drilling tool 54. Also, the valve 16 and the auxiliary drill section 14 will not be retrieved.

From the foregoing description of the drill bit 10 and the use thereof in the yformation of shot holes, yit will be readily apparent that a great saving will be effected. Not only is all of 'the drill string 56 and the main section 12 of the drill bit 10 retrieved, which in the case of drilling in soft formations constitutes the entire drilling .tool 54, ibut the entire drilling and pulling operation maybe accomplished `by a single crew in a single setup. This fin itself is a large cost factor. Further, in certain terrains it is extremely difficult to move in the drilling equipment and special transportation devices are required. Inasmuch as `there is no loss of the tubing 58, it will be seen that only that tubing 58 which is required during the actual drilling operation with a few spare sections, will be required "to Vbe moved into inaccessible areas. This provides a further saving. While with an individual shot hole 52 such a saving may not appear too great, it is to be understood that shot holes 52 are used for only one explosion and that hundreds of shot holes are drilled in a seismographic operation. Therefore, in View of the fact that many shot holes 52 are formed, it will be seen that the saving eifected by the use of the drill bit and the method of placing the explosive charge 60 and the removal of the drilling tool 54 prior to the explosion of the explosive charge 60 will be relatively great.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. In the drilling of shot holes with a drilling tool including a hollow drill string having a bit secured thereto, the bit having a flow passage communicating with the drill string to provide for circulation of drilling lluid through the drill string and bit, the method of charging a shot hole while the drilling tool remains in the shot hole comprising providing an explosive charge with an elongated length of detonator wire, lowering said explosive charge into the drilling tool through the ow passage and into the shot hole using said detonator wire, forming the upper end of said detonator wire into a large ball of a size to pass through the drilling tool and frictionally engage the interior of the drill string, releasing said detonator wire, pulling the drilling tool from the shot hole over said detonator wire.

2. The method `of drilling and charging a shot hole comprising providing a drilling `tool including a drill string and a drill bit on the lower end of said drill string, said drill bit having a flow passage therethrough of a size substantially equal to the internal cross section of said drill string for the circulation of drilling fluid through 40 said drill string and with said drilling tool, providing an explosive charge with an elongated length of detonator Wire, lowering said explosive charge into said drilling tool through said flow passage and into said shot hole using said detonator wire, forming the upper end of said detonator wire into a large ball of a size to pass through said drilling tool and frictionally engage the interior of said drill string, releasing said detonator wire, and pulling said drilling tool from said shot hole over said detonator w1re.

3. In the drilling of shot holes with a drilling tool including a hollow drill string having a bit secured thereto, the bit having a flow passage communicating with the drill string to provide for circulation of drilling fluid through the drill string and bit, the method of charging a shot hole while the drilling tool remains in the shot hole comprising lifting the drilling tool a slight distance above the bottom of the shot hole, removing a portion of the drilling tool to increase the cross-sectional area of the flow passage to permit the passage of au explosive charge through the drilling to a point therebelow, providing an explosive charge with an elongated length of detonator wire, lowering said explosive charge into the drilling tool through the flow passage and into the shot hole beneath the drilling tool using the detonator wire, forming the upper end of the detonator wire into a large ball of a size to pass through the drilling tool and frictionally engage the interior of the drill string, releasing the detonator wire, and pulling the drilling tool from the shot hole over the detonator wire with the explosive charge remaining at the bottom of the shot hole.

References Cited in the le of this patent UNITED STATES PATENTS 1,905,497 Peters Apr. 25, 1933 2,282,596 Wise et al. May 12, 1942 2,464,781 Baker Mar. 22, 1949 2,793,833 Daniel May 28, 1957 

